Appeals judges upheld his 20-year sentence for war crimes against Bosnian Muslims during the war in the Balkans in the 1990s, prompting Praljak to stand up and address the court in The Hague, Netherlands.

“Judges, Slobodan Praljak is not a war criminal,” he said. “With disdain, I reject this verdict.”

He then drank from what appeared to be a small vial, ignoring calls from the judge to sit down.

“I have taken poison,” he said, according to a court translator.

The judge suspended the hearing and Praljak was brought in for treatment, according to Reuters. He reportedly died in a hospital in The Hague.

Praljak was a former assistant minister of defense of Croatia, and later commander of the main staff of the former Croatian Defense Council, a militia operating in Bosnia. He was originally sentenced to 20 years in jail in 2013.

The Yugoslavia tribunal, created in 1993 by the United Nations Security Council, has prosecuted hundreds of people for war crimes and is scheduled to shut down at the end of this year.

The Yugoslav army targeted Bosnian Muslims and Croats in a brutal conflict that killed more than 100,000 people. The ICTY has played an integral role in shedding light on some of these atrocities, including the 1995 genocide in the town of Srebrenica and the use of rape as a weapon of war.

Gen. Ratko Mladic, known as the “Butcher of Bosnia,” was convicted last week of genocide, war crimes and crimes against humanity, and given a life sentence. “Everything that you have said is pure lies,” he yelled in response. “Shame on you.”